Conventionally, an exhaust purifying device provided in an exhaust passage of an internal combustion engine is constituted by including a carrier (a honeycomb carrier) in which an exhaust purifying catalyst is carried and a cylindrical case member adapted to house the carrier therein. In the case of housing the carrier within the case member, it is important to firmly hold the carrier within the case member. For this reason, it is known that a holding member commonly known as a mat is caused to lie between an inner circumferential surface of the case member and an outer circumferential surface of the carrier and a stopper member is provided on each edge periphery of inflow and outflow sides of exhaust in the carrier. A buffer member is inserted between the stopper member and the carrier (e.g., refer to Japanese published unexamined application No. 2013-160149).
In order to strengthen coupling of a ring-shaped stopper member with an edge inner circumferential surface of a cylindrical case member, when a contact area of both members is made larger, the case member is extended in the axial direction of the cylindrical body and as a result, the exhaust purifying device becomes longer as a whole and miniaturization of the device is inhibited. For this reason, in the exhaust purifying device of Japanese published unexamined application No. 2013-160149, one part of a ring-shaped stopper member is divided to have a C-shape. Once the C-shaped stopper member is reduced in diameter, it is then press-fitted into the edge section of the cylindrical case member. After press-fitting is completed, the diameter of the stopper member is increased to make a pressure contact with the inner circumferential surface of the case member. In addition, in such a pressure contact condition, the stopper member is welded to the edge section of the case member by welding. At this time, it is said that, since the stopper member is installed in such a position that it enters the inside from the edge section of the cylindrical case member, a total length of the exhaust purifying device is shortened.